1. Field of the Invention
The present invention relates to a starter equipped with a motor having a field coil, and an electromagnetic switch adapted to supply an electric current from a battery to the motor to start an engine through a pinion gear.
2. Description of the Related Art
A known conventional starter is equipped with a motor having an armature to which electricity is supplied from a battery through a brush and adapted to generate a torque in the armature, and an electromagnetic switch for ON/OFF-controlling the battery current caused to flow through the armature, with a part of a pigtail connected to the brush being formed of a low melting point material providing a fuse function (see, for example, JP 2003-148315 A).
In the above conventional starter, when the battery current is continuously supplied to the motor due to failure of the start switch, etc., the pigtail undergoes a fusing to thereby stop the supply of the electricity to the armature, whereby breakage of the starter is prevented.
Likewise, to prevent starter breakage, another known starter is equipped with a brush lead wire one end of which is mechanically and electrically connected to a brush and the other end of which is directly soft-soldered to a movable contact of an electromagnetic switch (see, for example, JP 2005-83259 A).
The pigtail as disclosed in JP 2003-148315 A is connected to a slidable brush, so it can happen that when, for example, the pigtail moves with the brush and comes close to a nearby component, an abnormal current flows to cause the pigtail, which has undergone a fusing, to come into contact with the nearby component to develop a short circuit, making it impossible to cut off the battery current.
In the brush lead wire as disclosed in JP 2005-83259 A, its melting temperature is determined by a soft solder material used, the melting point of which is usually low, so even when normal current is supplied thereto, the brush lead wire may undergo a fusing, making it impossible to start an engine.